title: Virus-poly(3,4-ethylenedioxythiophene) composite films for impedance-based biosensing.
abstract: Composite films composed of poly(3,4-ethylenedioxythiophene), PEDOT, and the filamentous virus M13-K07 were prepared by electrooxidation of 3,4-ethylenedioxythiophene (EDOT) in aqueous solutions containing 8 nM of the virus at planar gold electrodes. These films were characterized using atomic force microscopy and scanning electron microscopy. The electrochemical impedance of virus-PEDOT films increases upon exposure to an antibody (p-Ab) that selectively binds to the M13 coat peptide. Exposure to p-Ab causes a shift in both real (Z(RE)) and imaginary (Z(IM)) impedance components across a broad range of frequencies from 50 Hz to 10 kHz. Within a narrower frequency range from 250 Hz to 5 kHz, the increase of the total impedance (Z(total)) with p-Ab concentration conforms to a Langmuir adsorption isotherm over the concentration range from from 6 to 66 nM, yielding a value for K(d) = 16.9 nM at 1000 Hz.
authors.forename: Keith C
authors.initials: KC
authors.lastname: Donavan
authors.forename: Jessica A
authors.initials: JA
authors.lastname: Arter
authors.forename: Rosa
authors.initials: R
authors.lastname: Pilolli
authors.forename: Nicola
authors.initials: N
authors.lastname: Cioffi
authors.forename: Gregory A
authors.initials: GA
authors.lastname: Weiss
authors.forename: Reginald M
authors.initials: RM
authors.lastname: Penner
mesh_terms: D000906:Antibodies / Q000032:analysis / Q000276:immunology; D017104:Bacteriophage M13 / Q000737:chemistry* / Q000276:immunology; D015374:Biosensing Techniques / Q000379:methods*; D019086:Bridged Bicyclo Compounds, Heterocyclic / Q000737:chemistry*; D017097:Electric Impedance; D004595:Electroplating; D006046:Gold / Q000737:chemistry; D057230:Limit of Detection; D011108:Polymers / Q000737:chemistry*
chemical_list: D000906:Antibodies; D019086:Bridged Bicyclo Compounds, Heterocyclic; D011108:Polymers; C121383:poly(3,4-ethylene dioxythiophene); D006046:Gold